A063967 → basis A013611

nonnegative coefficients

Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means

Recurrence

\(P_{n}(x) = \left(2 + 4\,x\right)\,P_{n-2}(x) + \left(2 + 4\,x\right)\,P_{n-1}(x)\)

\(P_{1}(x) = 1\)

\(P_{2}(x) = 2 + 4\,x\)

Rows ?

n	x⁰	x¹	x²	x³	x⁴	x⁵	x⁶	x⁷	P_n(1)
1	1								1
2	2	4							6
3	6	20	16						42
4	16	80	128	64					288
5	44	288	688	704	256				1980
6	120	976	3104	4800	3584	1024			13608
7	328	3184	12640	26176	29696	17408	4096		93528
8	896	10112	48128	124928	190464	169984	81920	16384	642816

Show all 15 stored rows

Generated b-files: A057089 (row sums) ?

Computed in your browser ?

Technical details

Node id: n-2156f740e0c97180 · revision 1 · JSON
Definition source: derived:basis_map_A013611
Fingerprint: f6-5143ff9180de8713

Observed on the stored rows ?

Degrees: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 (affine: slope 1, intercept -1)
Palindromic rows: no
γ-positive (gamma_positive): no
Nonnegative coefficients (nonn): yes
Only rational roots (rr_by_factors: every nonzero row is a product of linear factors over ℚ): no

OEIS matches ?

A057089: row sums, 15 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS · generated b-file 200 terms from n = 0 ?

A generated b-file is computed from the node's definition along the row alignment of its OEIS link and starts at the entry's offset. It is an identification on a finite prefix, not a proof that the node and the OEIS entry agree for every n.

OEIS submission text ?

Fields to paste into an OEIS submission: the example %e, the formula %F and programs %t (Mathematica) and %o (PARI/GP) that list the same rows. For an OEIS link the row numbers, the offset and the orientation are those of the entry, as matched; the matched terms were compared with the published ones, which identifies the node with the entry on a finite prefix, not for every n. The PARI/GP program is not machine-checked here.

The atlas's own rows: n = 1, …, ascending powers of x

%e Example

Triangle begins:
   1:    1;
   2:    2,     4;
   3:    6,    20,     16;
   4:   16,    80,    128,      64;
   5:   44,   288,    688,     704,     256;
   6:  120,   976,   3104,    4800,    3584,    1024;
   7:  328,  3184,  12640,   26176,   29696,   17408,    4096;
   8:  896, 10112,  48128,  124928,  190464,  169984,   81920,   16384;
   9: 2448, 31488, 174720,  545280, 1044736, 1255424,  921600,  376832,   65536;
  10: 6688, 96576, 612096, 2231808, 5151232, 7791616, 7708672, 4800512, 1703936, 262144;

%F Formula

The row polynomials satisfy P(n,x) = (2+4*x)*P(n-2,x) + (2+4*x)*P(n-1,x) for n >= 3, with P(1,x) = 1, P(2,x) = 2 + 4*x.

%t Mathematica

P[1, x_] := 1;
P[2, x_] := 2 + 4*x;
P[n_, x_] := P[n, x] = Expand[(2 + 4*x)*P[n - 2, x] + (2 + 4*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten

%o PARI/GP

P(N) = {my(v = vector(N)); v[1] = 1; v[2] = 2 + 4*x; for(n = 3, N, my(i = n); v[i] = (2 + 4*x)*v[i - 2] + (2 + 4*x)*v[i - 1]); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i, v[i])))};
T(10)

Generated with polytool c48629374597.

Proved properties

Real-rooted. Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
Every polynomial of the sequence has only real roots, inside the stated interval.

by the cited steps: e-13a04d0165daacbb
Coefficients of one sign. Every nonzero row, n >= 1: the coefficients of P_n have one sign
All coefficients of each polynomial have the same sign (after x -> -x when alternating).

derived from the cited steps by a stated theorem: e-13a04d0165daacbb
Hadamard kernel (Malo). Rows P_n, n >= 1, are Hadamard kernels (preserve real-rootedness)
Multiplying the coefficients of any real-rooted polynomial termwise by those of a row (Hadamard product) gives a real-rooted polynomial again.

derived from the cited steps by a stated theorem: e-13a04d0165daacbb

Proof chains

1 incoming proof step. Each step is expanded back to the roots of the proof DAG, the theorem checks of a node's own rule. JSON

basis_map A013611 e-13a04d0165daacbb

Geometric basis map (elementary) polytool ?
- premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
  uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
  - basis_map A063967 e-6e2f4b29fae24343
    
    Affine-current basis map theorem polytool RealRooted orderTwoConstants_nonneg_iff ?
    
    premise (sequence): basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in [0, 0]
    
    no recorded property covers this requirement
  - basis_map A027466 e-07199d0e633dc35b
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 7]
    
    preserver_image affine, shift 0 e-12ad66072da87843
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    theorem_check ma_wang_interval e-32a5b77539bbfdf5 root: theorem check
    
    Ma–Wang interval theorem [MW08, Thm 2, Cor 3] RealRooted RealRooted.affineEndpointStep_closed ?
  - basis_map A038291 e-19f9843f81ec4d82
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 9]
    
    preserver_image affine, shift 0 e-61f403043a781326
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A038255 e-20a66a93533ac8e0
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 6]
    
    preserver_image affine, shift 0 e-cc7a67409dceb768
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A038279 e-2d6f22aa44a34472
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 8]
    
    preserver_image affine, shift 0 e-f5bf3eab46ece5d6
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A027465 e-300fe6b47fa78df1
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 3]
    
    preserver_image affine, shift 0 e-acc0c42734fdb8fc
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A038327 e-37edf5cceba94f47
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 12]
    
    preserver_image affine, shift 0 e-4d81c1e2745a9ed0
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A007318 e-50014fa936b4943d
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downward antidiagonals.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
    
    preserver_image reversal, shift -1 e-24564bef34b2c2e5
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Irregular triangle read by rows: T(n,k) = binomial(n-k, k), n >= 0, 0 <= k <= floor(n/2); or, coefficients of (one vers…
    uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    
    parent_provers paper_theorem e-0801036cdfff24d2 root: theorem check
    
    Parent-row provers of polytool polytool ?
    
    parent_provers paper_theorem e-0d3631d0f359c9ce root: theorem check
    
    Parent-row provers of polytool polytool ?
    
    gamma_polynomial scale 1, shift 0 e-a039cba7823b0b25
    
    Gamma criterion RealRooted IsGammaExpansion.isRealRooted_and_hasRootsNonpos_iff ?
    
    premise (sequence): delannoy
    uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    
    theorem_check liu_wang_derivative_lag e-15c233e4385971d1 root: theorem check
    
    Liu–Wang theorem with a lag row [LW07, Thm 2.1] RealRooted ?
    
    preserver_image reversal, shift 0 e-266d85ca03a298fa
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): delannoy
    uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    
    ↵ theorem_check liu_wang_derivative_lag e-15c233e4385971d1 (expanded above)
    
    basis_map A008288 e-e771e35dc9ee3fbd
    
    Affine-current basis map theorem polytool RealRooted orderTwoConstants_nonneg_iff ?
    
    premise (sequence): a(n) = 1 if n is of the form m(m+3)/2, otherwise 0.
    uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in [0, 0]
    
    no recorded property covers this requirement
    
    basis_map A008288 e-33dba7e79fe9caa8
    
    Affine-current basis map theorem polytool RealRooted orderTwoConstants_nonneg_iff ?
    
    premise (sequence): a(n) = 1 if n is of the form m(m+3)/2, otherwise 0.
    uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in [0, 0]
    
    no recorded property covers this requirement
    
    ↵ basis_map A008288 e-e771e35dc9ee3fbd (expanded above)
    
    ↵ basis_map A008288 e-33dba7e79fe9caa8 (expanded above)
    
    basis_map A007318 e-fcd19baf8f835cf0
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 1]
    
    preserver_image affine, shift 0 e-1365676e8cb0fd13
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
    
    preserver_image affine, shift 0 e-3c4e27dedb9c54a8
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downward antidiagonals.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-4, 0]
    
    theorem_check ma_wang_interval e-0178a3d1cd265fb6 root: theorem check
    
    Ma–Wang interval theorem [MW08, Thm 2, Cor 3] RealRooted RealRooted.affineEndpointStep_closed ?
    
    basis_map A026729 e-fa68694d112454ed
    
    Affine-current basis map theorem polytool RealRooted orderTwoConstants_nonneg_iff ?
    
    premise (sequence): basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in [0, 0]
    
    no recorded property covers this requirement
    
    ↵ theorem_check ma_wang_interval e-0178a3d1cd265fb6 (expanded above)
  - basis_map A038231 e-5c88965e8c99a752
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 4]
    
    preserver_image affine, shift 0 e-0e7024e7b55599e9
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A038303 e-78cb35d9024a5ff1
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 10]
    
    preserver_image affine, shift 0 e-25462190c1ff20a9
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A007318 e-933c6ae38be5f965
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downward antidiagonals.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
    
    ↵ preserver_image reversal, shift -1 e-24564bef34b2c2e5 (expanded above)
    
    ↵ basis_map A007318 e-fcd19baf8f835cf0 (expanded above)
    
    ↵ basis_map A026729 e-fa68694d112454ed (expanded above)
    
    ↵ theorem_check ma_wang_interval e-0178a3d1cd265fb6 (expanded above)
  - basis_map A038243 e-a054677672f9106d
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 5]
    
    preserver_image affine, shift 0 e-81aeef92852c73bb
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - basis_map A038207 e-a7cf73c813009d2a
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 2]
    
    ↵ preserver_image affine, shift 0 e-1365676e8cb0fd13 (expanded above)
    
    ↵ preserver_image affine, shift 0 e-3c4e27dedb9c54a8 (expanded above)
  - basis_map A027467 e-bfdacf28446aab8d
    
    Geometric basis map (elementary) polytool ?
    
    premise (sequence): basis-map coefficients of Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 15]
    
    preserver_image affine, shift 0 e-79b40901050ca651
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k) + T(n-1,k-1) + T(n-2,k-1) and T(0,0) = 1.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-5, -1]
    
    ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - ↵ theorem_check ma_wang_interval e-32a5b77539bbfdf5 (expanded above)
  - preserver_image affine, shift 0 e-e504746edac4d52e
    
    Affine, reversal and Möbius substitutions (elementary) polytool ?
    
    premise (sequence): Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downward antidiagonals.
    uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
    
    ↵ preserver_image reversal, shift -1 e-24564bef34b2c2e5 (expanded above)
    
    ↵ basis_map A007318 e-fcd19baf8f835cf0 (expanded above)
    
    ↵ basis_map A026729 e-fa68694d112454ed (expanded above)
    
    ↵ theorem_check ma_wang_interval e-0178a3d1cd265fb6 (expanded above)

Related sequences ?

Same fingerprint (1)

Equal up to content, sign, reversal and a small index shift.

A099040 → basis A013609

References

[LW07] Lily L. Liu and Yi Wang. A unified approach to polynomial sequences with only real zeros. Advances in Applied Mathematics, 38(4):542–560, May 2007. doi:10.1016/j.aam.2006.02.003
[MW08] Shi-Mei Ma and Yi Wang. q-Eulerian polynomials and polynomials with only real zeros. The Electronic Journal of Combinatorics, 15(1):Research Paper 17, January 2008. doi:10.37236/741